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    <h6 id="header">RMagick 0.0.0 User's Guide and Reference</h6>

    <div class="nav">&laquo;&nbsp;<a href="rvgtut.html">Prev</a> | <a href="index.html">Contents</a> | <a href="rvggroup.html">Next</a>&nbsp;&raquo;</div>

    <h1>class RVG <span class="superclass">&lt; Object</span></h1>

    <div id="toc">
      <h2>Table of Contents</h2>

      <h3>class methods</h3>

      <ul>
        <li><a href="#RVG_new">new</a></li>
      </ul>

      <h3>attributes</h3>

      <div class="toccol">
        <ul>
          <li><a href="#RVG_background_fill">background_fill=</a></li>

          <li>
            <a href="#RVG_background_fill_opacity">background_fill_opacity=</a>
          </li>

          <li><a href="#RVG_background_image">background_image=</a></li>

          <li><a href="#RVG_background_pattern">background_pattern=</a></li>

          <li><a href="#RVG_background_position">background_position=</a></li>
        </ul>
      </div>

      <div class="toccol">
        <ul>
          <li><a href="#RVG_canvas">canvas</a></li>

          <li><a href="#RVG_desc">desc, desc=</a></li>

          <li><a href="#RVG_height">height</a></li>

          <li><a href="#RVG_metadata">metadata, metadata=</a></li>
        </ul>
      </div>

      <div class="toccol">
        <ul>
          <li><a href="#RVG_title">title, title=</a></li>

          <li><a href="#RVG_width">width</a></li>

          <li><a href="#RVG_x">x</a></li>

          <li><a href="#RVG_y">y</a></li>
        </ul>
      </div>

      <h3>instance methods</h3>

      <div>
        <div class="toccol">
          <ul>
            <li><a href="#RVG_draw">draw</a></li>

            <li><a href="#RVG_g">g</a></li>

            <li><a href="#RVG_image">image</a></li>
          </ul>
        </div>

        <div class="toccol">
          <ul>
            <li>
              <a href="#RVG_preserve_aspect_ratio">preserve_aspect_ratio</a>
            </li>

            <li><a href="#RVG_rvg">rvg</a></li>

            <li><a href="#RVG_text">text</a></li>
          </ul>
        </div>

        <div class="toccol">
          <ul>
            <li><a href="#RVG_use">use</a></li>

            <li><a href="#RVG_viewbox">viewbox</a></li>
          </ul>
        </div>
      </div>

      <h3>shared methods</h3>

      <p>
        In addition to the methods listed above, <code>class RVG</code> also implements the <a href="rvgstyle.html">styles</a> method, the
        <a href="rvgshape.html">shape methods</a> and the <a href="rvgxform.html">transform methods</a>.
      </p>

      <h3>Units</h3>

      <div class="toccol">
        <ul>
          <li><a href="#units">Units conversion methods</a></li>
        </ul>
      </div>
    </div>

    <h2 class="methods">class methods</h2>

    <div class="sig">
      <h3 id="RVG_new">new</h3>

      <p>
        RVG.new(<span class="arg">width</span>=nil, <span class="arg">height</span>=nil) [ <span class="arg">{ |canvas| drawing method calls }</span> ] -&gt;
        <em>rvg</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Creates a container that can have its own coordinate system. Within the block, call drawing methods on <em>canvas</em> to render shapes, text, and
        raster images in the container.
      </p>

      <p>
        An RVG object is always the outermost container for a drawing. Call the
        <a href="#RVG_draw">draw</a> method on the returned RVG object to produce the final image.
      </p>

      <h4>Arguments</h4>

      <p>
        If the RVG object is the outermost container,
        <span class="arg">width</span> and <span class="arg">height</span> are required and specify the width and height of the final drawing in pixels. You can
        call <a href="#units">conversion methods</a> to use units such as inches and millimeters instead of pixels.
      </p>

      <p>
        Otherwise, <span class="arg">width</span> and <span class="arg">height</span> specify the area of the viewbox. If the RVG object will be used as an
        argument to the <a href="rvguse.html#use">use</a> method, then <span class="arg">width</span> and <span class="arg">height</span> may be omitted here,
        then specified as arguments to <code>use</code>.
      </p>

      <h4>Returns</h4>

      <p>An RVG object</p>

      <h4>Example</h4>

      <p>
        See the <a href="rvgtut.html">tutorial</a> for a simple example. The image below demonstrates an advanced use of <code>RVG.new</code>. This example
        creates an RVG object that draws an orange-and-green target. The <span class="arg">width</span> and <span class="arg">height</span> arguments are
        omitted in the <code>RVG.new</code> call. Instead, the viewport width and height are specified as arguments to 4 invocations of
        <a href="rvguse.html#use">use</a>. Each <code>use</code> specifies a different viewport size, so the same RVG object draws 4 different-sized targets.
      </p>

      <p>Click the image to see the example script.</p>

      <p>
        <a href="javascript:popup('nested_rvg.rb.html')"><img src="ex/nested_rvg.gif" title="Click to see the example script" alt="nested RVG example" /></a>
      </p>

      <h4>See also</h4>

      <p><a href="rvggroup.html">Group</a></p>
    </div>

    <h2 class="methods">attributes</h2>

    <div class="sig">
      <h3 id="RVG_background_fill">background_fill=</h3>

      <p>
        <span class="arg">canvas</span>.background_fill =
        <span class="arg">value</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Specify a background fill color. The attribute value may be either a
        <a href="struct.html#Pixel">pixel</a> or a <a href="imusage.html#color_names">color name.</a> The default fill color is "#00000000". This color is
        usually called "none". This attribute has no effect on nested RVG objects.
      </p>

      <h4>Example</h4>
      <pre>
canvas.background_fill = 'white'
</pre
      >

      <h4>Returns</h4>
      <span class="arg">value</span>
    </div>

    <div class="sig">
      <h3 id="RVG_background_fill_opacity">background_fill_opacity=</h3>

      <p>
        <span class="arg">canvas</span>.background_fill_opacity =
        <span class="arg">value</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Specify the opacity of the background fill color when the
        <a href="#RVG_background_fill">background fill</a> is not the default. The value is a number between 0.0 (fully transparent) and 1.0 (fully opaque). The
        default is 1.0. The attribute is ignored unless <code>background_fill</code> is specified. This attribute has no effect on nested RVG objects.
      </p>

      <h4>Example</h4>
      <pre>
canvas.background_fill = 'white'
canvas.background_fill_opacity = 0.50
</pre
      >

      <h4>Returns</h4>
      <span class="arg">value</span>
    </div>

    <div class="sig">
      <h3 id="RVG_background_image">background_image=</h3>

      <p>
        <span class="arg">canvas</span>.background_image =
        <span class="arg">image</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Specify an image to be used as the canvas background. The value is an
        <a href="image1.html#new">Image</a> object. This attribute has no effect on nested RVG objects.
      </p>

      <h4>Example</h4>
      <pre>
canvas.background_image = Magick::Image.read('myBackground.gif').first
</pre
      >

      <h4>Returns</h4>
      <span class="arg">image</span>

      <h4>See also</h4>

      <p><a href="#RVG_background_position">background_position=</a></p>
    </div>

    <div class="sig">
      <h3 id="RVG_background_pattern">background_pattern=</h3>

      <p>
        <span class="arg">canvas</span>.background_pattern =
        <span class="arg">fill</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>Specify an <a href="struct.html#fill">Fill object</a> to fill the canvas background. This attribute has no effect on nested RVG objects.</p>

      <h4>Example</h4>
      <pre>
canvas.background_pattern = Magick::GradientFill.new(0, 0, 0, 100, "#900", "#000")
</pre
      >

      <h4>Returns</h4>
      <p>a Fill object</p>
    </div>

    <div class="sig">
      <h3 id="RVG_background_position">background_position=</h3>

      <p>
        <span class="arg">canvas</span>.background_position =
        <span class="arg">pos</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        If the dimensions of the image specified by
        <a href="#RVG_background_image">background_image</a> do not exactly match the canvas dimensions, this attribute specifies how to position the image on
        the background. This attribute has no effect on nested RVG objects.
      </p>

      <h4>Argument</h4>
      The value of <span class="arg">pos</span> can be any one of the following symbols :

      <dl>
        <dt>:scaled</dt>

        <dd>The image is scaled to fit. The image proportions are not retained.</dd>

        <dt>:tiled</dt>

        <dd>The image is tiled across the background.</dd>

        <dt>:fit</dt>

        <dd>
          The image is scaled to fit. The image proportions are retained. Any part of the background that is not covered by the image is colored with the
          <a href="#RVG_background_color">background color</a>.
        </dd>
      </dl>

      <h4>Example</h4>
      <pre>
canvas.background_image = Magick::Image.read('myBackground.gif').first
canvas.background_position = :scaled
</pre
      >

      <h4>Returns</h4>
      <span class="arg">pos</span>
    </div>

    <div class="sig">
      <h3 id="RVG_canvas">canvas</h3>

      <p><span class="arg">rvg</span>.canvas -&gt; image</p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        After the <a href="#RVG_draw">draw</a> method has been used, returns the rendered image. This is the same image that
        <a href="#RVG_draw">draw</a> returns.
      </p>

      <h4>Returns</h4>

      <p>An image</p>
    </div>

    <div class="sig">
      <h3 id="RVG_desc">desc, desc=</h3>

      <p>
        <span class="arg">rvg</span>.desc -&gt; <span class="arg">string</span><br />
        <span class="arg">rvg</span>.desc = <span class="arg">string</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>
      Use the <code>desc</code> attribute to assign a text description to the drawing. The description will be assigned to the "desc" property of the resulting
      image. This attribute has no effect on nested RVG objects.
    </div>

    <div class="sig">
      <h3 id="RVG_height">height</h3>

      <p>
        <span class="arg">rvg</span>.height -&gt;
        <span class="arg">height</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>The height of the RVG object in user coordinates.</p>

      <h4>See also</h4>

      <p><a href="#RVG_width">width</a></p>
    </div>

    <div class="sig">
      <h3 id="RVG_metadata">metadata, metadata=</h3>

      <p>
        <span class="arg">rvg</span>.metadata -&gt; <span class="arg">string</span><br />
        <span class="arg">rvg</span>.metadata = <span class="arg">string</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>
      Use the <code>metadata</code> attribute to assign additional metadata to the drawing. The metadata string will be assigned to the "metadata" property of
      the resulting image. This attribute has no effect on nested RVG objects.
    </div>

    <div class="sig">
      <h3 id="RVG_title">title, title=</h3>

      <p>
        <span class="arg">rvg</span>.title -&gt; <span class="arg">string</span><br />
        <span class="arg">rvg</span>.title = <span class="arg">string</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>
      Use the <code>title</code> attribute to assign a title to the drawing. The title will be assigned to the "title" property of the resulting image. This
      attribute has no effect on nested RVG objects.
    </div>

    <div class="sig">
      <h3 id="RVG_width">width</h3>

      <p><span class="arg">rvg</span>.width -&gt; <span class="arg">width</span></p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>The width of the RVG object in user coordinates.</p>

      <h4>See also</h4>

      <p><a href="#RVG_height">height</a></p>
    </div>

    <div class="sig">
      <h3 id="RVG_x">x</h3>

      <p><span class="arg">rvg</span>.x -&gt; <span class="arg">x-offset</span></p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        If this RVG object is nested within another RVG object, returns the x-offset in user coordinates from the upper-left corner of the enclosing RVG object.
      </p>

      <h4>See also</h4>

      <p><a href="#RVG_y">y</a></p>
    </div>

    <div class="sig">
      <h3 id="RVG_y">y</h3>

      <p><span class="arg">rvg</span>.y -&gt; <span class="arg">y-offset</span></p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        If this RVG object is nested within another RVG object, returns the y-offset in user coordinates from the upper-left corner of the enclosing RVG object.
      </p>

      <h4>See also</h4>

      <p><a href="#RVG_x">x</a></p>
    </div>

    <h2 class="methods">instance methods</h2>

    <div class="sig">
      <h3 id="RVG_draw">draw</h3>

      <p><span class="arg">rvg</span>.draw -&gt; image</p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>Causes all the drawing objects that have been added to the canvas to be rendered.</p>

      <p>
        Regardless of the order in which methods were called,
        <code>draw</code> executes the methods in this order:
      </p>

      <ol>
        <li>transforms, in the order they were called.</li>

        <li><code>viewbox</code> and <code>preserve_aspect_ratio</code></li>

        <li>styles</li>

        <li>nested groups, RVG objects, shapes, text, and images, in the order they were added to the containing object</li>
      </ol>

      <p>Nested groups and RVG objects also follow this sequence.</p>

      <h4>Returns</h4>

      <p>An image</p>

      <h4>Example</h4>
      <pre>
      img = rvg.draw
      img.write('myDrawing.jpg')
</pre
      >
    </div>

    <div class="sig">
      <h3 id="RVG_g">g</h3>

      <p><span class="arg">rvg.</span>g [{|<span class="arg">grp</span>| ...}] -&gt; <span class="arg">group</span></p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Calls <a href="rvggroup.html#new">RVG::Group.new</a> to construct a group and adds it to the enclosing RVG object. Yields to a block if one is present,
        passing the new group as an argument.
      </p>

      <h4>Returns</h4>

      <p>Returns the new group, so <code>RVG::Group</code> methods can be chained to this method.</p>
    </div>

    <div class="sig">
      <h3 id="RVG_image">image</h3>

      <p>
        <span class="arg">rvg.</span>image(<span class="arg">raster_image</span>, <span class="arg">width</span>=nil, <span class="arg">height</span>=nil,
        <span class="arg">x</span>=0, <span class="arg">y</span>=0) -&gt; <span class="arg">image</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>Calls <a href="rvgimage.html#new">RVG::Image.new</a> to construct an image and adds it to the enclosing RVG object.</p>

      <h4>Returns</h4>

      <p>Returns the new image, so <code>RVG::Image</code> methods can be chained to this method.</p>

      <h4>Notes</h4>

      <p>An <code>RVG::Image</code> object is <em>not</em> the same as a <a href="image1.html">Magick::Image</a> object!</p>
    </div>

    <div class="sig">
      <h3 id="RVG_preserve_aspect_ratio">preserve_aspect_ratio</h3>

      <p>
        <span class="arg">rvg</span>.preserve_aspect_ratio(<span class="arg">align</span>, <span class="arg">meet_or_slice</span>='meet') [{|<span class="arg"
          >self</span
        >| ...}] -&gt; <span class="arg">self</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        If you use the <a href="#RVG_viewbox">viewbox</a> method and the user coordinate system does not scale uniformly to the default coordinate system (for
        example, the width and height of the RVG object is 4x3 and the user coordinate system is 16x9), use the <code>preserve_aspect_ratio</code> method to
        specify whether or not the content is stretched to fit. If not, you can specify how to fit the content into the space.
      </p>

      <p><code>Preserve_aspect_ratio</code> yields to a block if one is present, passing <span class="arg">self</span> as an argument.</p>

      <h4>Arguments</h4>

      <dl>
        <dt>align</dt>

        <dd>
          When the value of the <code>meet_or_slice</code> argument is 'meet' or 'slice', this argument controls the placement of the content within the
          viewport. The <code>align</code> argument is the concatenation of an <em>x</em>-alignment and a <em>y</em>-alignment. The values are shown in these
          lists:

          <h6><em>x</em>-alignment</h6>

          <dl>
            <dt>xMin</dt>

            <dd>align the minimum <em>x</em> value of the content with the left corner of the viewport.</dd>

            <dt>xMid</dt>

            <dd>vertically center the content within the viewport.</dd>

            <dt>xMax</dt>

            <dd>align the maximum <em>x</em> value of the content with the right corner of the viewport.</dd>
          </dl>

          <h6><em>y</em>-alignment</h6>

          <dl>
            <dt>YMin</dt>

            <dd>align the minimum <em>y</em> value of the content with the top of the viewport.</dd>

            <dt>YMid</dt>

            <dd>horizontally center the content within the viewport.</dd>

            <dt>YMax</dt>

            <dd>align the maximum <em>y</em> value of the content with the bottom of the viewport</dd>
          </dl>
        </dd>

        <dt>meet_or_slice</dt>

        <dd>
          This argument can have one of these three values:

          <dl>
            <dt>'none'</dt>

            <dd>The content is scaled as necessary so that it fits exactly within the viewport. The aspect ratio is <em>not</em> maintained.</dd>

            <dt>'meet'</dt>

            <dd>
              The content is scaled as necessary so that the larger dimension exactly fits the viewport. There may be some unused space in the viewport. The
              aspect ratio is maintained.
            </dd>

            <dt>'slice'</dt>

            <dd>
              The content is scaled as necessary so that the smaller dimension exactly fits the viewport. Some of the content in the larger dimension may be cut
              off. The aspect ratio is maintained.
            </dd>
          </dl>
        </dd>
      </dl>

      <h4>Example</h4>

      <p>
        <a href="javascript:popup('preserve_aspect_ratio.rb.html')"
          ><img src="ex/preserve_aspect_ratio.gif" title="Click to see the example script" alt="preserve_aspect_ratio example"
        /></a>
      </p>

      <h4>Returns</h4>

      <p><span class="arg">Self</span>, so other <code>RVG</code> methods can be chained to this method.</p>

      <h4>See Also</h4>

      <p><a href="#RVG_viewbox">viewbox</a></p>
    </div>

    <div class="sig">
      <h3 id="RVG_rvg">rvg</h3>

      <p>
        <span class="arg">rvg</span>.rvg(<span class="arg">width</span>, <span class="arg">height</span>, <span class="arg">x</span>=0,
        <span class="arg">y</span>=0) [{|<span class="arg">new_rvg</span>| ...}] -&gt; <em>self</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        This method constructs a new RVG object and adds it to the enclosing RVG object. Each nested RVG object can use the
        <a href="#RVG_viewbox">viewbox</a> method to define its own coordinate system. The <code>rvg</code> method yields to a block, passing the nested RVG
        object as an argument. Within the block, any drawing objects added to the nested RVG object are rendered within the nested RVG object's viewport.
      </p>

      <h4>Arguments</h4>

      <dl>
        <dt>width, height</dt>

        <dd>Specifies the viewport width and height. The units are in the user coordinate system of the parent container.</dd>

        <dt>x, y</dt>

        <dd>The x- and y-axis offsets of the viewport upper-left corner. The units are in the user coordinate system of the parent container.</dd>
      </dl>

      <h4>Example</h4>

      <p>
        See the example for
        <a href="#RVG_preserve_aspect_ratio">preserve_aspect_ratio</a>.
      </p>

      <h4>Returns</h4>

      <p>The <code>RVG</code> object, so other <code>RVG</code> methods can be chained to this method.</p>
    </div>

    <div class="sig">
      <h3 id="RVG_text">text</h3>

      <p>
        <span class="arg">rvg.</span>text(<span class="arg">x</span>=0, <span class="arg">y</span>=0, <span class="arg">text</span>=nil) [{|<span class="arg"
          >text</span
        >| ...}] -&gt; <em>text</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Calls <a href="rvgtext.html#new">RVG::Text.new</a> to construct a text object and adds it to the enclosing RVG object. Yields to a block if one is
        present, passing the new text object as an argument.
      </p>

      <h4>Returns</h4>

      <p>The <code>RVG::Text</code> object, so other <code>RVG::Text</code> methods can be chained to this method.</p>
    </div>

    <div class="sig">
      <h3 id="RVG_use">use</h3>

      <p>
        <span class="arg">rvg</span>.use(<span class="arg">obj</span>, <span class="arg">x</span>=0, <span class="arg">y</span>=0,
        <span class="arg">width</span>=nil, <span class="arg">height</span>=nil) -&gt; <em>use</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>Calls <a href="rvguse.html#new">RVG::Use.new</a> to construct a <code>use</code> object and adds it to the RVG object.</p>

      <p>
        When the referenced argument is another RVG object,
        <span class="arg">width</span> and <span class="arg">height</span> can be used to specify the width and height of the viewport. If present and non-nil,
        these arguments override any width and height specified when the RVG object was created. You must specify the viewport size either when creating the RVG
        object or when referencing it with <code>use</code>.
      </p>

      <h4>Examples</h4>

      <p>See <a href="rvguse.html#new">RVG::Use.new</a></p>

      <h4>Returns</h4>

      <p>The <code>RVG::Use</code> object, so other <code>RVG::Use</code> methods can be chained to this method.</p>
    </div>

    <div class="sig">
      <h3 id="RVG_viewbox">viewbox</h3>

      <p>
        <span class="arg">rvg</span>.viewbox(<span class="arg">min_x</span>, <span class="arg">min_y</span>, <span class="arg">width</span>,
        <span class="arg">height</span>) [{|<span class="arg">self</span>| ...}] -&gt; <em>self</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        The area of the RVG object is called the <em>viewport</em>. By default the origin of the coordinate system for an RVG object is (0,0). The user
        coordinates are pixels and the width and height are established by the <span class="arg">width</span> and <span class="arg">height</span> arguments to
        <code>RVG.new</code>.
      </p>

      <p>
        Use the <code>viewbox</code> method to superimpose a user coordinate system on the viewport. The <code>viewbox</code> method lets you set up a
        coordinate system using the units of your choice.
      </p>

      <p>The <code>viewbox</code> method yields to a block if one is present, passing <code>self</code> as an argument.</p>

      <h4>Arguments</h4>

      <dl>
        <dt>min_x, min_y</dt>

        <dd>The minimum <em>x</em>-coordinate and <em>y</em>-coordinate of the user coordinate system.</dd>

        <dt>width, height</dt>

        <dd>The width and height of the user coordinate system.</dd>
      </dl>

      <h4>Example</h4>

      <p>
        In the following examples, because the <code>viewbox</code> method specifies the dimensions of the coordinate system, the dimensions specified for the
        graphic objects can remain the same while the size of the canvas changes.
      </p>

      <p>
        <strong>Rendered into a 300x200 viewport</strong
        ><a href="javascript:popup('view_box.rb.html')"
          ><img src="ex/view_box_300x200.gif" title="Click to see the example script" alt="viewbox 300x200 example"
        /></a>
      </p>

      <p>
        <strong>Rendered into a 150x200 viewport</strong
        ><a href="javascript:popup('view_box.rb.html')"
          ><img src="ex/view_box_150x200.gif" title="Click to see the example script" alt="viewbox 150x200 example"
        /></a>
      </p>

      <h4>Returns</h4>

      <p><span class="arg">Self</span>, so other <code>RVG</code> methods may be chained to <code>viewbox</code>.</p>

      <h4>See Also</h4>

      <p><a href="#RVG_preserve_aspect_ratio">preserve_aspect_ratio</a></p>
    </div>

    <h2 id="units" class="methods">Units</h2>

    <div style="margin-left: 235px; margin-top: 1em">
      <p>
        RVG supports a subset of the unit identifiers defined by the SVG specification. In RVG, unit identifiers are methods in the Float and Integer classes.
        The units are (for the most part) defined in terms of "dots per inch," accordingly, the unit identifier methods are added only if the value
      </p>
      <pre>
    Magick::RVG.dpi = NN
</pre
      >

      <p>is defined, where NN is the number of "dots" (pixels) per inch you wish to use. (Hint: 90 is a good default.)</p>

      <p>For example, to specify a length of 10 inches, you can use</p>
      <pre>
    Magick::RVG.dpi = 90
    length = 10.in  # =&gt; 900 pixels
</pre
      >

      <p>
        If the dpi is defined, the following methods are added to
        <code>Float</code> and <code>Integer</code>
      </p>

      <dl>
        <dt>px</dt>

        <dd>Pixel. The default unit of measurement.</dd>

        <dt>in</dt>

        <dd>Converts inches to pixels</dd>

        <dt>mm</dt>

        <dd>Converts millimeters to pixels</dd>

        <dt>cm</dt>

        <dd>Converts centimeters to pixels</dd>

        <dt>pt</dt>

        <dd>Converts points to pixels. There are 72 points to the inch.</dd>

        <dt>pc</dt>

        <dd>Converts picas to pixels. There are 12 points to the pica.</dd>

        <dt>deg</dt>

        <dd>Degrees. The default unit of rotation.</dd>

        <dt>rad</dt>

        <dd>Converts radians to degrees.</dd>

        <dt>grad</dt>

        <dd>Converts grads to degrees. There are 400 grads in a circle.</dd>

        <dt>pct</dt>

        <dd>This conversion takes an numeric argument and returns a percentage of the argument. For example 20.pct(150) -&gt; 30</dd>
      </dl>

      <p>SVG also supports <em>em</em> and <em>ex</em>, which are measurements based on the font size. RVG does not.</p>
    </div>

    <p class="spacer">&nbsp;</p>

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